Protein called epil/placentin, process for the preparation of this protein and pharmaceutical composition containing such, DNA coding for said protein

ABSTRACT

The subject of the invention is a new protein called EPIL or placentin, its analogs showing EPIL/placentin-type activity, obtained by deletion and/or substitution. The invention also concerns a DNA molecule coding for a EPIL/placentin-type polypeptide. It finally concerns a pharmaceutical composition containing EPIL/placentin or a EPIL/placentin analog.

This application is a divisional of Ser. No. 08/482,842, filed Jun. 7, 1995, now U.S. Pat. No. 5,910,480.

The present invention concerns a new protein called placentin or EPIL, its analogs, the procedures for their preparation and their applications.

Insulin, IGF1, IGF2 and relaxin belong to a family of peptide hormones having certain common structures and functions, particularly their influence upon cell proliferation, development, differentiation and metabolism.

Insulin is well known as being an endocrine pancreatic hormone regulating energy metabolism. Growth factors of insulin-IGF-1 type are growth promoting peptides involved in endocrine, paracrine and autocrine regulation of cell growth and which are expressed in numerous Tissues. IGF2 has similar properties but is expressed in higher quantities during the prenatal period and is considered as being a fetal growth factor.

Relaxin induces remodeling of connective tissue in the reproductive tract and inhibits uterine contractions. Its functional role in the brain, where extensive expression has been obtained, remains to be elucidated.

Recently, Ley-I-Ls were added to this family which are currently cloned in cDNA form and whose biological activity remains to be determined. This peptide family commonly presents structural characteristics defined by the position of different cysteines essential for the formation of a tertiary structure.

Insulin, which is the prototype for this family, comprises two peptide A and B chains connected by disulfide bridges. It is coded by a mRNA which is translated into preproinsulin. The peptide signal, like the connecting C peptide, are excised by post-translational modification; this also applies to relaxin although the IGFs are matured differently without elimination of the C peptide and remain as a single chain. It has been shown that all the members of this family attach themselves to cell surface receptors. These receptors have been identified by molecular cloning and characterized in detail for insulin and IGF. They belong to the superfamily of tyrosine protein kinase receptors (Tyr-PK receptors) which comprises growth factor receptors and their oncogene analogs such as c-neu/erb-B-2 (EGF receptor), c-met (hepatocyte growth factor receptor), fms (CSF-1 receptor) and trk (NGF receptor).

The transduction route of the intracellular signal for these receptors is characterized by tyrosine-kinase activity which produces autophosphorylation of the tyrosine residues on the receptor followed by a chain of events corresponding to phosphorylations. This includes, in particular, the activation of IRS-1 (particularly for insulin and IGF), P13K, Shc, GBRZ, Sos, Ras, Raf and the kinase mitogenesis activating protein (MAP) especially when the cascade of phosphorylation affects different cell processes such as transcription.

The pleiotropic physiological effects of this cascade of signals are generally the subject of intense research.

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1A and 1B depict a DNA sequence and corresponding amino acid sequence for EPIL/placentin.

FIGS. 2A and 2B depict the detailed structure of EPIL/placentin including the signal sequence (position −17 to −1), the B chain (position 1 to 41), the C peptide (position 42-92), and the A chain (position 93-122).

The present invention concerns, more particularly, a new molecule of this insulin family which is called hereinafter placentin or EPIL (Early Placenta Insulin-Like peptide) whose amino acid sequence and the DNA sequence which codes for this protein corresponds to the ID 1 sequence.

EPIL/Placentin was isolated from a cDNA bank of cytotrophoblastic cells prepared from placenta taken during the first trimester of pregnancy. Northern blot analysis (performed on very wide sampling of normal tissues) revealed detectable RNA levels only in placental tissue.

The amino acid sequence obtained shows an arrangement of cysteine residues for protein according to the invention that is characteristic of the insulin family.

The treatment of target cells with media fed with cell cultures expressing the recombinant protein seems to induce a pattern of tyrosine phosphorylation similar to that observed after treatment with insulin.

Finally, EPIL/placentin induces DNA synthesis.

This is why the present invention concerns, more particularly, a protein called EPIL/placentin, a protein with a formula corresponding to sequence ID 1, also represented in FIG. 1, and its analogs showing placentin-type activity and obtained by deletion and/or substitution.

On sequence ID 1, the structure of EPIL/placentin corresponds to the amino acid structure following methionine at position 36 as far as the amino acid at position 174.

The references to the DNA sequences of EPIL/placentin correspond to this sequence.

The nucleic sequences existing before the first presumed ATG (underlined) and after the stop codon are in small letters.

EPIL/Placentin analogs are proteins or peptides which have high ammo acid homology, particularly over 60% homology, preferably 80% with the compound corresponding to sequence ID 1, which could be obtained by deletion or by substitution while preserving the essential characteristics of EPIL/placentin. These analogs shall sometimes be called “EPIL/placentin-type compounds”.

In particular, the present invention concerns fragments which show certain epitopes characteristic of EPIL/placentin activity, in particular EPIL/placentin-type proteins which have at least the first 20 amino acids of the N-terminal extremity of sequence ID 1.

The present invention evidently concerns EPIL/placentin or its analogs in glycosylated or non-glyosylated form and the proteins with or without the disulfide bridges of the original protein. Indeed, this protein may be prepared by extraction using biological samples but shall be preferably obtained via techniques using generic engineering and its secondary structures may vary in accordance with the host organism.

The invention also concerns a molecule chosen among:

(a) the DNA sequence of the ID 1 sequence,

(b) DNA sequences likely to hybridize to the preceding sequence and which code for a EPIL/placentin-type polypeptide, and

(c) DNA sequences which taking into account the genetic code correspond to sequences (a) or (b) and which code for a EPIL/placentin-type polypeptide.

In particular, the invention concerns the DNA sequence corresponding to sequence ID 1.

Evidently, the DNA sequences previously mentioned may be genomic or genomic-type sequences, that is to say that certain elements may be separated by introns which will be excised to lead to the expression of mature EPIL/placentin.

The preceding DNA sequences may be incorporated into cloning or expression vectors of EPIL/placentin or its analogs, preferably under the control of elements assuring their expression in a defined host cell.

The systems of expression in prokaryotic or eucaryotic cells are well known to men of the art. These may in particular concern systems of plasmid type or viral type comprising promoters assuring expression in the host cell and also provided with the necessary terminal elements.

But they may also concern integration vectors which may comprise their own system of expression or else be designed to integrate into the chromosomes in places where they come under the promotion of a chromosome promotor, in particular in the case of prokaryotic cells, using the homologous recombination technique.

The present invention also concerns host cells characterized in that they comprise a self-replicating vector expressing EPIL/placentin or a EPIL/placentin analog in accordance with the invention or a DNA sequence in accordance with the invention incorporated into a chromosome and expressing EPIL/placentin or a EPIL/placentin analog.

As previously indicated, these may be eukaryotic cells, in particular mammalian cells of CHO cell type, or cultured cells of other types more appropriate to the preparation of EPIL/placentin in its mature form; but it is also possible to contemplate using bacterial cells for example: in this case it may be appropriate to subject the protein obtained to additional modifications.

These techniques are again known to men of the art and shall not be described more fully, except within the context of certain examples below.

The cells thus transformed by a self-replicating vector expressing the protein or having integrated the sequence expressing the protein in its chromosomes may be used by culture in a process permitting the preparation of EPIL/placentin or its analogs.

This particularly concerns a process for the preparation of EPIL/placentin or its analogs characterized by the culturing of cells from which EPIL/placentin or its analogs shall be extracted either directly or from the culture medium.

EPIL/Placentin may in particular be extracted by inmuno-purification.

The present invention also concerns recombination products obtained through the previously performed process.

In certain cases, the protein may be prepared in fused form, in particular when a peptide-type analog of EPIL/placentin is involved, or when fusion with this protein provides easier access to the action site of EPIL/placentin or its analogs, or when, in certain cases, this protein can be used to deceive certain natural systems by giving the protein of interest longer life.

Finally, the present invention relates to pharmaceutical compositions using EPIL/placentin or its analogs as an active ingredient.

As indicated, EPIL/placentin has multiple activities, in particular it may, like other type 1 human growth factors, offer cardiac-related activity, in particular for the treatment and prevention of certain heart disorders such as acute cardiac failure.

This protein or some of its analogs may offer growth factor and lactation type activity. Also, the products may be used in the regeneration process of nerve, muscle, skin or bone tissues, especially in degenerative or endocrine pathologies, traumatic lesions or viral illnesses.

Finally, EPIL/placentin or its analogs may offer action in connection with the control of all phenomena relating to conception in man or animal.

The present invention also concerns antibodies and more particularly specific monoclonal antibodies of EPIL/placentin or its analogs, and an in vitro diagnosis method which uses EPIL/placentin or its analogs and/or corresponding antibodies to detect abnormal levels of EPIL/placentin in samples that may or may not be physiological.

DNA fragments corresponding to the previously mentioned sequences may be integrated into “sense” or “antisense” treatment strategy; EPIL/placentin or its analogs could be integrated into a strategy targeting certain pharmaceutically active molecules towards receptors of EPIL/placentin or its analogs.

The detailed structure of EPIL/placentin called EPIL corresponds to sequence of FIG. 2 [SEQ ID NOS.: 4-14] that is to say a peptide signal at position −17 to −1 [SEQ ID NOS.: 5 & 6], a B chain 1 to 41 [SEQ ID NOS.: 7 & 8], a connecting C peptide from 42 to 92 [SEQ ID NOS.: 9 & 10] then an A chain from 93 to 122 [SEQ ID NOS.: 11 & 12].

This structure relates EPIL to proinsulin or prorelaxin.

In particular, the position of the disulfide bridges must lead to an insulin-type three-dimensional structure.

Other characteristics and advantages of the present invention will appear on reading the following examples making reference to sequences ID 1 and FIG. 2 [SEQ ID NOS.: 4-14] corresponding to the sequence of EPIL/placentin and of the human gene coding for this protein.

EXAMPLES

The identification of EPIL/placentin is the outcome of specific research seeking to determine the molecules involved in cell growth and/or in neoplasic processes.

Although placenta is a normal tissue, its constituting cells have numerous properties in common with neoplasic cells, in particular with invasive, highly mitotic cytotrophoblasts which may penetrate the maternal tissue. These trophoblasts are an inexhaustible source of growth factors, hormones and growth factor receptors in particular.

Current studies show that the genes preferably expressed in trophoblastic cells may also be preferably expressed in neoplasic cells.

However taking into account that placenta, and in particular trophoblasts, remain under full control during normal pregnancy, the trophoblastic molecules corresponding to this control are highly interesting candidates as anticancerous agents or likely to control the cancerisation process.

This is why the isolation method used is a cDNA subtraction method having recourse to PCR technology on young trophoblasts. This permitted the detection of genes which are overexpressed in these cells and which may play a role in cellular growth and regulation.

Material and Methods

Tissues

Placentas of 5 to 12 weeks, full term placentas and surgical samples of normal and tumorous tissues were refrigerated immediately (within 10 minutes after surgery) and preserved in liquid nitrogen until RNA preparation. These tissue collections were obtained and used in accordance with protocols approved by the Committees of the different hospitals.

Cells

The human cell lines used throughout this study and their histological origins are as follows: gestational choriocarcinoma (JAr and JFG-3); hepatocellular carcinoma (PLC/PRF/5 and Hep G2); colon adenocarcinoma (LSI80); ovarian carcinoma (OVI/p, OVIVCR), the OVI/VCR cell line is derived from OVI/p and is resistant to vincristin; epidermoid carcinoma (A431); lung carcinoma (A427); epithelioid carcinoma of the cervix (HeLa); mammary carcinoma (McF7, MDA-MB-361, SK-BRA-3, BTu-20 and BTu-474); mammary cells transformed by SV-40 (HBL-100): neuroblastoma cell line (SHSY-5Y); normal fibroblast cell line (CCL-137).

All these cell lines being available to ATCC with the exception of IGR/OVI (OVI/p) and OVI/VCR.

These cell lines are cultured in a DMEM or RPMI-1460 medium (Gibco-BRL Laboratories, Gaithersburg, Mass.) supplemented with 10% fetal calf serum inactivated by heat, 10 μm non essential amino acids, 4 mM glutamin, 100 U/ml penicillin and 100 μg/ml streptomycin at 37° C. with 5% CO2.

Isolation of the Cyrotrophoblasts

The cytotrophoblasts are purified as described by Kliman et al. Endocrinology, 118: 1567-1582, 1986. Briefly, the villi tissue of first trimester placenta are dispersed with trpysin and deoxyribonuclease-1. The dispersed cells are then purified through a 5-70% Percoll gradient (Pharmacia). The 1040-1060 g/ml density band is collected. Microscropic examination shows that it comprises cytotrophoblastic cells with less than 5% contamination with non-trophoblastic cells such as macrophages, fibroblasts and endorehlial cells.

Preparation of RNA

Total RNA is prepared from preconfluent cell cultures or refrigerated tissues using guanidinine isothiocyanate and ultracentrifugation on a cesium chloride gradient by adapting the protocol described by Chirgwin et al. The polysome RNAs associated with the endoplasmic reticulum membranes (MB-RNA) are purified as described previously. After trypsination and purification through a Percoll gradient, the cytotrophoblastic cells art homogenized, then the MB-RNAs are isolated on a sucrose gradient to which is added a vanadyl ribonucleoside complex as ribonuclease inhibitor.

cDNA Synthesis and PCR Amplification

0.1 μg MB-RNA are dissolved in 5 μl DEPC treated water and denatured with 0.1 M MeHgOH and β-mercaptoethanol. The first cDNA strand is synthesized with the reverse transcriptase of avian myoblastosis virus (Invitrogen kit, San Diego) using the modified dT primer indicated below (Frohman et al. Proc. Natl. Acad. Sci. U.S.A., 85: 8998-9002, 1988). The RNA-cDNA heteroduplexes of size ranging from 0.5 to 2 kb are electroeluted after migration in 2% agarose gel. A dG oligo tail is added to the 3′ end of the first cDNA strand with the terminal deoxynucleotide transferase and the RNA is eliminated by alkaline hydrolysis. The cDNAs are amplified with non specific primers including restriction sites for Notl and Sall enzymes.

The sequence [SEQ ID NO.: 15] of the T primer used for reverse transcription and PCR is as follows:

5′-GACTCGAGTCGACATCGATTTTTTTTTTTTTTTTT-3′

The C primer [SEQ ID NO.: 16] is identical to that described by Loh et al., (Science, 243: 217-220, 1989):

5′GCATCGGCGCGGCCGCGGAGGCCCCCCCCCCCCCC-3′

The reaction mixture comprises 1.25 mM of each of the 4 triphosphate desoxyribonucleotides, 0.5 μM of each primer and 2.5 units of Taq polymerase in 50 mM Kcl-10 mM Tris-HCl (pH 8.3)—3.5 mM MgCl2-0.01% gelatin. Amplification is carried out in a thermal cycler for 25 cycles of 20 seconds at 94° C., 30 seconds at 55° C. and 1 minute at 72° C. The products are loaded on 1% agarose gel at low fusion. The 0.5-2 kb region is then excised and reamplified under the same conditions. The products are precipitated, fully digested with Notl and Sall, the sizes are selected as previously and electroeluted from agarose, precipitated and quantified.

The total cDNA of full term placenta and T lymphocytes activated with phyrohemagglutinin and cultivated for several days in the presence of IL2 was prepared using a double strand cDNA synthesis method.

Construction of the Subtracted cDNA Bank

Subtraction hybridization is performed as described by Klickstein (Klickstein et al. Current protocols in molecular biology, pp 5.8.9.-5.8.15 Wiley Interscience, 1989). 0.2 μg cDNA from cytotrophoblastic cells amplified by PCR are left to digest with Notl and Sall, mixed with 8 μg cDNA of activated T lymphocytes and 8 μg cDNA of full term placenta digested with Alul and Rsal, dissolved in 40 μl hybridization buffer (50% deionized formamide; 10 mM sodium phosphate buffer, pH 7; 5×SSC, 0.1% SDS; 10 mM EDTA), denatured for 5 minutes at 98° C. and incubated for 24 hours at 37° C.

The sequences common to target and competitor are collected to form duplexes between the short fragments (Alu/Rsa, competitor) and the long fragments (Not/Sal of the target) by inhibiting the formation of cohesive ends. Complementary cDNA strands specifically expressed in the young cytotrophoblasts permit the regeneration of the Notl and Sall cohesive ends for unidirectional cloning in the pBSKII sites+vector phagemid (Stratagene).

Bank Sifting

The subtracted cDNA bank is spread over a gelose culture medium and the recombinant colonies are collected and cultured in the LB medium then amplified by PCR. The plasmid DNAs, prepared by the boiled minipreparation method (Del Sal G. et al. Nucleic Acids Res., 16: 9878, 1988) and digested with Notl and Sall or the insert products amplified by PCR using the original primers, are analyzed by Southern blotting on 1.2% agarose gels. The average size of inserts is between 500 and 1000 nucleotides. The gels are transferred in duplicate onto nylon membranes (Hybond N, Amersham) in an alkaline buffer. The probes used for hybridization are total cDNAs synthesized from young placentas, full term placentas and activated T lymphocytes 32P-labeled (Amersham) by random multiple priming. Hybridization is carried out for 18 hours at 42° C. followed by stringent washing in 0.1×SSC at 50° C. and autoradiography.

Northern Blot Analysis

5 μg of total RNA taken from different tissues and cell lines are analyzed on 1% agarose gel containing 2.2 M of formaldehyde. On completion of electrophoresis, the gel is rinsed with bi-distilled water and treated with 10×SSC for 30 minutes. The RNA is then transferred to a reinforced nitrocellulose membrane (Schleicher & Schuell, Dassel) in the 20×SSC transfer buffer for 18 hours. The transferred RNAs are fixed to the membranes by UV radiation before hybridization. The probes used to hybridize the membranes are excised inserts 32P-labeled by random multiple priming, or single strand probes generated by PCR using a universal antisense primer. Hybridization is carried out overnight at 42° C. followed by stringent washing in 0.1×SSC at 50° C. and autoradiography.

DNA Sequencing and Analysis

The plasmid DNAs are prepared using the boiled minipreparation method. DNA sequencing is performed with the Sequenase kit, version 2.0 (U.S. Biochemical). The primers are either universal M13, T3, or T7 primers or specific internal primers. Reaction products are analyzed on gels containing 6% acrylamide and 50% urea. The sequences obtained are compared with the sequences of the different data banks.

Analysis

The clones which do not give any hybridization signal with standardized probes are analyzed by partial sequencing and comparison with these data banks.

One of the clones corresponding to EPIL/placentin corresponds to the amino acid sequence corresponding to sequence ID 1.

Total RNA and polyA samples prepared from normal or transformed cell lines and from corresponding tissues are subjected to Northern blotting with labeled, single strand, antisense EPIL/placentin cDNA probes. Hybridization signals are detected solely in the placentas, especially early pregnancy placentas and are practically non-existent in the other tissues as shown in the table given below (Table 1):

TABLE 1 YOUNG PLACENTA ++++ FULL TERM PLACENTA ++ NORMAL LIVER − TUMOROUS LIVER − NORMAL BLADDER − TUMOROUS BLADDER − NORMAL OMENTUM − TUMOROUS OMENTUM − NORMAL ESOPHAGUS − TUMOROUS ESOPHAGUS − NORMAL COLON − TUMOROUS COLON − NORMAL STOMACH − NORMAL CERVIX UTERI − NORMAL ENDOMETRIUM − NORMAL OVARY − TUMOROUS BREAST − TUMOROUS GANGLION − NORMAL SPLEEN − NORMAL RECTUM − TUMOROUS RECTUM − NORMAL FALLOPIAN TUBE − NORMAL SKIN − NORMAL MYOMETRIUM − NORMAL ADRENAL GLAND − NORMAL THYROID − TUMOROUS THYROID −

Studies carried out on murine and simian products show analogies indicating significant functional similarities between species.

EPIL/Placentin Expression

For the eukaryotic expression of EPIL/placentin, cDNA was inserted into the pEK-CMV expression vector in the sense and antisense position.

Two cell types were used to examine the possible effects of post-translational modifications inherent to cell types. COS-7 monkey kidney cells were transfected by DEAE for transient expression while the human trophoblastic cells transformed by SV40 (3AsubE) were transfected by CaPO4 for stable, transient expression.

The COS-7 and 3AsubE cells do not express any detectable level of EPIL/placentin mRNA with northern blot. The transfected cells are fed with serum-free culture medium

The media fed with sense or antisense transfected cells are analyzed to detect the presence of recombinant proteins.

The biological activity of the recombinant protein is analyzed on different target cells considering that the specific receptors may exist or that the protein may attach itself to other receptors for molecules of proximal structure as was observed for insulin and IGF.

Preliminary results suggest that EPIL/placentin would induce tyrosine phosphorylation of cellular proteins and would have biological activity on trophoblastic cells growth.

16 1 615 DNA Unknown CDS (1)..(615) Description of Unknown OrganismEPIL - Early Placenta Insulin-Like Peptide 1 agt ctg gag ccc aga agg gac aca cca gca cag tct ggt agg cta cag 48 Ser Leu Glu Pro Arg Arg Asp Thr Pro Ala Gln Ser Gly Arg Leu Gln 1 5 10 15 cag caa gtc tct aaa gaa agg ctg aga aca ccc aga aca gga gag ttc 96 Gln Gln Val Ser Lys Glu Arg Leu Arg Thr Pro Arg Thr Gly Glu Phe 20 25 30 agg tcc agg atg gcc agc ctg ttc cgg tcc tat ctg cca gca atc tgg 144 Arg Ser Arg Met Ala Ser Leu Phe Arg Ser Tyr Leu Pro Ala Ile Trp 35 40 45 ctg ctg ctg agc caa ctc ctt aga gaa agc cta gca gca gag ctg agg 192 Leu Leu Leu Ser Gln Leu Leu Arg Glu Ser Leu Ala Ala Glu Leu Arg 50 55 60 gga tgt ggt ccc cga ttt gga aaa cac ttg ctg tca tat tgc ccc atg 240 Gly Cys Gly Pro Arg Phe Gly Lys His Leu Leu Ser Tyr Cys Pro Met 65 70 75 80 cct gag aag aca ttc acc acc acc cca gga ggg tgg ctg ctg gaa tct 288 Pro Glu Lys Thr Phe Thr Thr Thr Pro Gly Gly Trp Leu Leu Glu Ser 85 90 95 gga cgt ccc aaa gaa atg gtg tca acc tcc aag aac aaa gat gga caa 336 Gly Arg Pro Lys Glu Met Val Ser Thr Ser Lys Asn Lys Asp Gly Gln 100 105 110 gcc tta ggt acg aca tca gaa ttc att cct aat ttg tca cca gag ctg 384 Ala Leu Gly Thr Thr Ser Glu Phe Ile Pro Asn Leu Ser Pro Glu Leu 115 120 125 aag aaa cca ctg tct gaa ggg cag cca tca ttg aag aaa ata ata ctt 432 Lys Lys Pro Leu Ser Glu Gly Gln Pro Ser Leu Lys Lys Ile Ile Leu 130 135 140 tcc cgc aaa aag aga agt gga cgt cac aga ttt gat cca ttc tgt tgt 480 Ser Arg Lys Lys Arg Ser Gly Arg His Arg Phe Asp Pro Phe Cys Cys 145 150 155 160 gaa gta att tgt gac gat gga act tca gtt aaa tta tgt aca tag tag 528 Glu Val Ile Cys Asp Asp Gly Thr Ser Val Lys Leu Cys Thr 165 170 175 agt aat cat gga ctg gac atc tca tcc att ctc ata tgt att ctc aat 576 Ser Asn His Gly Leu Asp Ile Ser Ser Ile Leu Ile Cys Ile Leu Asn 180 185 190 gac aaa ttc act gat gcc caa tta aat gat tgc tgt tta 615 Asp Lys Phe Thr Asp Ala Gln Leu Asn Asp Cys Cys Leu 195 200 205 2 139 PRT Unknown Description of Unknown OrganismEPIL - Early Placenta Insulin-Like Peptide 2 Met Ala Ser Leu Phe Arg Ser Tyr Leu Pro Ala Ile Trp Leu Leu Leu 5 10 15 Ser Gln Leu Leu Arg Glu Ser Leu Ala Ala Glu Leu Arg Gly Cys Gly 20 25 30 Pro Arg Phe Gly Lys His Leu Leu Ser Tyr Cys Pro Met Pro Glu Lys 35 40 45 Thr Phe Thr Thr Thr Pro Gly Gly Trp Leu Leu Glu Ser Gly Arg Pro 50 55 60 Lys Glu Met Val Ser Thr Ser Lys Asn Lys Asp Gly Gln Ala Leu Gly 65 70 75 80 Thr Thr Ser Glu Phe Ile Pro Asn Leu Ser Pro Glu Leu Lys Lys Pro 85 90 95 Leu Ser Glu Gly Gln Pro Ser Leu Lys Lys Ile Ile Leu Ser Arg Lys 100 105 110 Lys Arg Ser Gly Arg His Arg Phe Asp Pro Phe Cys Cys Glu Val Ile 115 120 125 Cys Asp Asp Gly Thr Ser Val Lys Leu Cys Thr 130 135 3 29 PRT Unknown Description of Unknown OrganismEPIL - Early Placenta Insulin-Like Peptide 3 Ser Asn His Gly Leu Asp Ile Ser Ser Ile Leu Ile Cys Ile Leu Asn 1 5 10 15 Asp Lys Phe Thr Asp Ala Gln Leu Asn Asp Cys Cys Leu 20 25 4 934 DNA Unknown Description of Unknown OrganismEPIL - Early Placenta Insulin-Like peptide 4 aggtcagttc tatttttatt tcatctaagc aaaggacatt aaaaattacc attattttag 60 taagcataaa aatagtatta caggaggaaa gttaagaaaa agaagtagaa caaccaaatt 120 caaaacaagc aaagtgcagc agcacattgg gagcaaagag ggatatgaga gtgtgggtag 180 ggcaagtagg gagactaaat aagaactgag ggagaaagtt ccttgtaggt gggtgggaaa 240 ggggtggact gacaccattg acgccaaagc tgagtatagc cctaagccaa ataaatgcct 300 gatgaaggca tgcagaaagc agtctggagc ccagaaggga cacaccagca cagtctggta 360 ggctacagca gcaagtctct aaagaaaggc tgagaacacc cagaacagga gagttcaggt 420 ccaggatggc cagcctgttc cggtcctatc tgccagcaat ctggctgctg ctgagccaac 480 tccttagaga aagcctagca gcagagctga ggggatgtgg tccccgattt ggaaaacact 540 tgctgtcata ttgccccatg cctgagaaga cattcaccac caccccagga gggtggctgc 600 tggaatctgg acgtcccaaa gaaatggtgt caacctccaa caacaaagat ggacaagcct 660 taggtacgac atcagaattc attcctaatt tgtcaccaga gctgaagaaa ccactgtctg 720 aagggcagcc atcattgaag aaaataatac tttcccgcaa aaagagaagt ggacgtcaca 780 gatttgatcc attctgttgt gaagtaattt gtgacgatgg aacttcagtt aaattatgta 840 catagtagag taatcatgga ctggacatct catccattct catatgtatt ctcaatgaca 900 aattcactga tgcccaatta aatgattgct gttt 934 5 157 DNA Unknown CDS (107)..(157) Description of Unknown OrganismEPIL - Early Placenta Insulin-Like peptide 5 cagtctggag cccagaaggg acacaccagc acagtctggt aggctacagc agcaagtctc 60 taaagaaagg ctgagaacac ccagaacagg agagttcagg tccagg atg gcc agc 115 Met Ala Ser 1 ctg ttc cgg tcc tat ctg cca gca atc tgg ctg ctg ctg agc 157 Leu Phe Arg Ser Tyr Leu Pro Ala Ile Trp Leu Leu Leu Ser 5 10 15 6 17 PRT Unknown Description of Unknown OrganismEPIL - Early Placenta Insulin-Like Peptide 6 Met Ala Ser Leu Phe Arg Ser Tyr Leu Pro Ala Ile Trp Leu Leu Leu 1 5 10 15 Ser 7 123 DNA Unknown CDS (1)..(123) Description of Unknown OrganismEPIL - Early Placenta Insulin-Like peptide 7 caa ctc ctt aga gaa agc cta gca gca gag ctg agg gga tgt ggt ccc 48 Gln Leu Leu Arg Glu Ser Leu Ala Ala Glu Leu Arg Gly Cys Gly Pro 1 5 10 15 cga ttt gga aaa cac ttg ctg tca tat tgc ccc atg cct gag aag aca 96 Arg Phe Gly Lys His Leu Leu Ser Tyr Cys Pro Met Pro Glu Lys Thr 20 25 30 ttc acc acc acc cca gga ggg tgg ctg 123 Phe Thr Thr Thr Pro Gly Gly Trp Leu 35 40 8 41 PRT Unknown Description of Unknown OrganismEPIL - Early Placenta Insulin-Like Peptide 8 Gln Leu Leu Arg Glu Ser Leu Ala Ala Glu Leu Arg Gly Cys Gly Pro 1 5 10 15 Arg Phe Gly Lys His Leu Leu Ser Tyr Cys Pro Met Pro Glu Lys Thr 20 25 30 Phe Thr Thr Thr Pro Gly Gly Trp Leu 35 40 9 153 DNA Unknown CDS (1)..(153) Description of Unknown OrganismEPIL - Early Placenta Insulin-Like peptide 9 ctg gaa tct gga cgt ccc aaa gaa atg gtg tca acc tcc aac aac aaa 48 Leu Glu Ser Gly Arg Pro Lys Glu Met Val Ser Thr Ser Asn Asn Lys 1 5 10 15 gat gga caa gcc tta ggt acg aca tca gaa ttc att cct aat ttg tca 96 Asp Gly Gln Ala Leu Gly Thr Thr Ser Glu Phe Ile Pro Asn Leu Ser 20 25 30 cca gag ctg aag aaa cca ctg tct gaa ggg cag cca tca ttg aag aaa 144 Pro Glu Leu Lys Lys Pro Leu Ser Glu Gly Gln Pro Ser Leu Lys Lys 35 40 45 ata ata ctt 153 Ile Ile Leu 50 10 51 PRT Unknown Description of Unknown OrganismEPIL - Early Placenta Insulin-Like Peptide 10 Leu Glu Ser Gly Arg Pro Lys Glu Met Val Ser Thr Ser Asn Asn Lys 1 5 10 15 Asp Gly Gln Ala Leu Gly Thr Thr Ser Glu Phe Ile Pro Asn Leu Ser 20 25 30 Pro Glu Leu Lys Lys Pro Leu Ser Glu Gly Gln Pro Ser Leu Lys Lys 35 40 45 Ile Ile Leu 50 11 93 DNA Unknown CDS (1)..(93) Description of Unknown OrganismEPIL - Early Placenta Insulin-Like peptide 11 tcc cgc aaa aag aga agt gga cgt cac aga ttt gat cca ttc tgt tgt 48 Ser Arg Lys Lys Arg Ser Gly Arg His Arg Phe Asp Pro Phe Cys Cys 1 5 10 15 gaa gta att tgt gac gat gga act tca gtt aaa tta tgt aca tag 93 Glu Val Ile Cys Asp Asp Gly Thr Ser Val Lys Leu Cys Thr 20 25 30 12 30 PRT Unknown Description of Unknown OrganismEPIL - Early Placenta Insulin-Like Peptide 12 Ser Arg Lys Lys Arg Ser Gly Arg His Arg Phe Asp Pro Phe Cys Cys 1 5 10 15 Glu Val Ile Cys Asp Asp Gly Thr Ser Val Lys Leu Cys Thr 20 25 30 13 48 DNA Unknown Description of Unknown OrganismEPIL - Early Placenta Insulin-Like peptide 13 gtgagagccc tggactacca aacaatcaga atgagggctg aaaaaaca 48 14 47 DNA Unknown Description of Unknown OrganismEPIL - Early Placenta Insulin-Like peptide 14 acatgaatgt ttttcctcac ctttcattcc tctcttttac ttcacag 47 15 35 DNA Unknown Description of Unknown OrganismEPIL - Early Placenta Insulin-Like peptide 15 gactcgagtc gacatcgatt tttttttttt ttttt 35 16 35 DNA Unknown Description of Unknown OrganismEPIL - Early Placenta Insulin-Like peptide 16 gcatcggcgc ggccgcggag gccccccccc ccccc 35 

What is claimed is:
 1. An isolated DNA molecule comprising a DNA sequence which encodes EPIL/placentin protein having sequence ID 2 or analogs thereof having EPIL/Placentin-type action and obtained by deletion and/or substitution.
 2. An isolated DNA molecule comprising the nucleotide sequence of sequence ID
 1. 3. An expression vector for the expression of EPIL/placentin or analogs thereof having EPIL/placentin-type action, said vector comprising a DNA sequence encoding EPIL/placentin having sequence ID 2 or a DNA sequence encoding analogs thereof obtained by deletion and/or substitution.
 4. A host cell comprising the expression vector of claim
 3. 5. The host cell according to claim 4, wherein said host cell is a eukaryotic cell.
 6. The host cell according to claim 4, wherein said host cell is a bacterium.
 7. A process for the preparation of EPIL/placentin or analogs thereof having EPIL/placentin-type action, said process comprising the steps of (a) culturing a host cell according to claim 4; and (b) extracting EPIL/placentin or analogs thereof directly from the host cells.
 8. A process for the preparation of EPIL/placentin or analogs thereof having EPIL/placentin-type action, said process comprising the steps of (a) culturing a host cell according to claim 4; and (b) extracting EPIL/placentin or analogs thereof from the culture medium. 